ULTRAFAST OPTICAL PULSE NOISE SUPPRESSION USING A NONLINEAR SPECTRAL FILTER - 23 DB REDUCTION OF FIBER LASER 1 F NOISE/

Nonlinear spectral filtering provides a simple method for reducing noi se in optical pulses to below the shot noise level. We show its effect iveness for excess noise reduction in an ultrafast optical pulse train by demonstrating 23 dB reduction of low frequency 1/f noise in pulses from a passively mode-locked erbium-doped fiber laser. The noise redu ction is achieved by spectrally filtering pulses propagated as soliton s through a 1.5 km length of optical fiber. (C) 1998 American Institut e of Physics. [S0003-6951(98)01540-X].